Question

i have the answer but the problem but no explanation.. i need to know how to solve this. how do i get there. thanks.

4x2 = -8x -1
the answer comes out to this fraction -2 ±√3
________
2

Answer 1

and the problem... here is a picture just in case

Answer 2

use the quadratic formula after getting all terms on one side 4x2+8x+1 so a=4, b=8, and c=1 plug into qf

Answer 3

did you take a look at the picture? it didnt type out correctly. sorry. i really appreciate your help.

Answer 4

I understood the problem..do you know the quadratic formula?

Answer 5

not really

Answer 6

ok I will type it out

Answer 7

thank you so much

Answer 8

\[-b \pm \sqrt{b ^{2}-4ac}/2a\]

Answer 9

2a is in the denominator so substitute a, b, and c

Answer 10

\[-8 \pm \sqrt{64-16}/ 8\]

Answer 11

\[-8\pm \sqrt{48}/8 = -8\pm \sqrt{16*3} /8 -8\pm4\sqrt{3} /8\]

Answer 12

I skipped the initial step of plugging in the values for a, b, and c do you get that part?

Answer 13

yes i do thank you

Answer 14

so do you understand it

Answer 15

its for friend, but yes i think so. im passing the info along. thank you for your time.

Answer 16

ok you're very welcome

Answer 17

one last question.. how did you know that the qf was necessary? just in case other problems like these come up. how can i decipher whether i need it or not.

Answer 18

if you can't solve the quadratic equation by factoring then your other options are by completing the square or the quadratic formula

Answer 19

not sure if youre still there, but one thing my friend didnt understand was how it was simplified to the final answer. isnt the 4 outside the square root technically tied to it and you can't really simplify it?

Answer 20

The simplification was valid. The 48 inside the radical was factored to 16 and 3, the square root of 16 was accomplished by moving the 4 outside of the radical leaving only the square root of 3 within the radical.

Answer 21

The simplification of\[-8\pm(4\sqrt{3})/8=-4(2\pm \sqrt{3})/8=(-2\pm \sqrt{3})/2\]